Directory signs are known and used in a wide variety of applications. These signs typically list persons or departments within an organization, and identify by room number or other information the particular locations of those places. Directory signs can range in size and construction from the one-of-a-kind directory custom designed for installation in a single location such as the lobby of a building, to signs of relatively standard size and configuration and intended for use in various applications. The present invention is primarily concerned with signs of the latter kind.
Typical conventional directory signs usually are rectangular in overall shape. A rectangular frame defines the periphery of the sign, and one or more panel members mounted on the peripheral frame provide support for the directory message board itself or for individual message strips containing the name of each person or office identified by the directory. The directory sign also may have one or more center supports intermediate the ends of the sign, depending on the overall length of the sign. Some directory signs are available in standard rectangular shapes to accommodate conventional applications. However, it is known to construct signs of desired width and height by using various standard components provided for that purpose. These sign components typically include edge members that can be cut to fit the height and width of a desired sign, and corner members adapted to join together the edge members in a fixed angular relation. Because most directory signs are rectangular, these edge members are fight-angle corner members adapted to join the confronting ends of adjacent edge members for connecting those members to form a sign frame having a rectangular overall shape. One or more message panels then is mounted on the overall sign frame fabricated from those components.
Directory signs and the like constructed from standard components permit a measure of customized design at reasonable cost, because those signs are assembled from components produced for the purpose and require no custom manufactured components. However, practical considerations limit the overall shape of such signs to rectangular shapes, namely, signs having four sides joined together by right-angle corner elements made for the purpose. Although the signs and their construction are not inherently limited to rectangular configurations formed by right-angle corners, constructing signs of non-rectangular polygonal configurations would require producing and stocking corner members in a wide variety of configurations other than fight angles. For example, signs having a parallelogram construction would require corner members having two different complementary angular shapes, namely, two acute-angle corners and two complementary obtuse-angle corners. Moreover, the conventional sign construction is not immediately adaptable to producing directory signs having a nonrectangular orthogonal shape, because the inside right-angle corners of nonrectangular orthogonal signs require corner angle members of different construction from the conventional outside corner angles.